Purification and Some Properties of a Soluble DNA‐Dependent RNA Polymerase from Nuclei of Human Placenta

Abstract

More than 75% of the RNA polymerase activity of isolated nuclei from human placental tissue was found in the supernatant (20 min at 40000Xg) after incubation of the nuclear suspension for 24 hours at 0°, followed by 15 min at 37° and a further 15 min at 37° in the presence of 120 mM ammonium sulphate. Chromatography of this soluble preparation on DEAE cellulose (0.64 mequiv./g) was carried out using a linear gradient from 100 to 500 mM ammonium sulphate. RNA polymerase activity, eluted at 300 mM ammonium sulphate, was fully dependent on added DNA template. Some properties of human RNA polymerase at various stages of purification are described. The process of solubilization is discussed. Copyright © 1969, Wiley Blackwell. All rights reserved